Serious Science: is there alien life in the universe? Part 1

As we stare out into the void of space, sift through strands of DNA and samples from the deepest seas & oceans, we search for clues as to what life is and why life even exists. But before we can begin our search out there in the ink black of the wide beyond, we must first understand life itself right here on Earth…

In this first installment, I’ll be looking at how powerful a force life is here on Earth and explore the prospects of life existing elsewhere in the universe.

I recently watched several talks from the TED conferences which got me thinking about a number of themes that are a constant fascination to me, revolving principally around life and the universe.

I won’t say biology and astrophysics, since I’m not qualified in either of those fields, despite these two disciplines forming the backdrop to life and the universe respectively.

Life

I truly believe that life is both a force and an inevitable function of nature. Beyond any emotions we might share with other mammals, beyond even the desire to live is the need to survive, or to be more accurate, to be survived by.

The chemical destiny of all life

Within every living cell are the mechanisms primed to manipulate, sort and organize the very chemicals that make life possible.

Acting as both the engine and the index of life itself, DNA (Deoxyribonucleic Acid) is an amazingly delicate yet resoundingly robust structure that allows for the full diversity of life we see here on Earth, along with all life that has ever existed.

As sophisticated biological process go, DNA is both elegant and ancient. The functions it is part of and required to perform rank it highly amongst the most complex operations any man-made computer might hope to achieve.

But despite its apparent complexity, life is of reducible complexity. What that means is, living organisms are an amalgam of components, all of which are themselves often comprised of yet smaller components. When these components are broken down, their complexity is reduced, also. At which point, we’re then better able to understand how those basic components work and how such complexity arose in the first place.

This is a simplification of course, but it’s enough for you to understand that life isn’t so complex that such things cannot arise by entirely natural forces.

To put it another way, there are no gods — only chemicals, environmental variables and time enough to allow for such things as amino acids to form, offering a platform onto which the forces of nature built all living things.

Life as an inevitable process

It’s my opinion that life is an inevitable process of the universe. I see life as inevitable as galactic, stellar and planetary formation, and their motions.

You see, life persists in almost any environment. Even the most baron, hostile environments on Earth harbour life.

In the 500 million years or so it took for the Earth to cool down after its initial formation, life emerged. Even if life was introduced from elsewhere, it’s unlikely the conditions of the early Earth would have been suitable. So those panspermiatic life forms would have had to adapt and evolve:

“Panspermia is the hypothesis that ‘seeds’ of life exist already all over the Universe, that life on Earth may have originated through these ‘seeds’, and that they may deliver or have delivered life to other habitable bodies.”

Most common theories of how life came into being here on Earth centre around the warm, humid conditions of the early Earth. However, there are other more intriguing theories; such as one regarding how life might have evolved in ice:

Given that both warm and cold conditions have their own unique influence on the formation on the key building blocks of life, might there not be an argument for a two-stage process? Some elements forming during the initial period of the warmer while others formed during colder times?

However, my theory is but amateur conjecture.

Life at the extremes

More evidence of the truly persistent nature of life can be found in those frozen and aridly dry regions of Earth, where it would appear that life has no place. Such organisms are known as extremophiles, who make their home in some of the most hostile conditions on Earth.

In some cases, organisms exist in environments not too dissimilar to those of the very early Earth; anaerobic places, like deep layers of sludge on the oceans’ floor, devoid of oxygen and light.

These places may well harbour specimens of life that have experienced almost no change since those first cellular organisms emerged over 3 billion years ago.

And most tantalizing of all, the hunt is on to find single-celled organisms that are so ancient they predate the evolutionary development of death. If such organisms do indeed exist, buried under layer upon layer of dense sludge, then they would be truly immortal.

“A hydrothermal vent is a geyser on the seafloor. It continuously spews super-hot, mineral-rich water that helps support a diverse community of organisms. Although most of the deep sea is sparsely populated, vent sites teem with a fascinating array of life. Tubeworms and huge clams are the most distinctive inhabitants of Pacific Ocean vent sites, while eyeless shrimp are found only at vents in the Atlantic Ocean.”

Even at the crushing depths of over 2,000 meters below the surface of the ocean, hidden in otherwise desolate regions of the sea floor, these vents belch out super heated water at temperatures as high as 400°C (750°F), yet the water does not boil at these depths because of the tremendous pressure from the weight of the ocean above.

The life that persists around these deep sea vents isn’t restricted to chemosynthetic bacteria (those that use heat instead of light to derive nutrients from chemicals, rather than from the light of the sun, which is photosynthetic) although such organisms do form the very base of the food chain. These hydrothermal vents are an oasis in the ocean floor wasteland they’re situated in, providing life for a number of larger animals, such as the aforementioned shrimp, clams, lobster and a variety of fish.

“Scientists have discovered bacteria swarming in the toxic sediment beneath underground tanks that have leaked radioactive waste at the Hanford nuclear reservation, home to some of the most highly contaminated soil in the world.”

If life is able to thrive in such fantastically hostile environments, albeit relatively simple life, life can thrive almost anywhere in the universe.

And if life can also form in cold environments, then there is great hope for moons such as Titan and Europa. Indeed, it is theorized that Europa has a liquid ocean beneath its shell of ice. Maybe at the bottom of those oceans lurk hydrothermal vents.

In the second installment, I’ll be looking at the prospect of other intelligent life in the universe, our place in the grand scheme of things, and how we as a species may well be at a crossroads in our destiny…

Comment and be known

If it happened here, then why not elsewhere? Out of all the billions of planets that have existed, still exist and will exist in the future, then surely chances are that life has, did, will emerge elsewhere. But, this is to assume, that the set of circumstances that gave rise to life on earth, you know Sagan’s primordial soup, was not somehow unique.

It really is just possible however that there are no other cool blue planets (i.e. ones with the just right conditions) for life elsewhere, never have been, and never will be again. And, even if there are then the chances of us ever reaching or contacting them directly are even smaller.

It’s all the more reason to focus on the wonders of our own little blue place in the universe, marvel at its wonders and protect its biodiversity, ecosystems and wild places.

db

PS You may have guessed I prefer biology of astrobiology. Nice article, by the way

I have to disagree with David’s points above, because we have already found that there was at one point basic life forms on Mars. That right there proves that Sagan’s primordial soup is not unique to our planet. Perhaps the conditions on Mars were not “perfect” enough to allow life to evolve to anything intelligent, but it did prove (at least to me) that it is very possible to have intelligent life forms even within our own galaxy.

I also liked that you did not just limit to what is out there beyond Earth, but you also chose to look at things much closer to home. Life at the bottom of the oceans fascinate me, there is still a great deal we have to explore here at home on our planet.

Sorry Paula but we are yet to find any definitive evidence of life anywhere else in the universe. It is certainly possible we might and I was not setting the stage for any kind of anthropocentric argument or anything like that. I’d love us to find the proverbial little green men, I just don’t think it’s going to happen.

David – I could have sworn I heard that evidence of small plant life was found on Mars. I apologize if that is not the case – I’m not too certain about little green men myself, those silver ones could be out there tho!

Wayne… Hmmm I’m thinking I need to dig further into your blog – I do know that you do the occasional science piece, I just thought of your ‘thing’ as having to do more with SEO, Google, Microsoft, blogging, etc. But, I am off to read those which you pointed out right now!

Paula – definitely not. If they’d actually found life on Mars, we’d never have heard the end of it. The latest item on space.com talks about a future manned mission possibly finding evidence and that human observation will be essential to any definitive verification of vital signs…but we’ve not had them yet. Anything we observe from here could easily be a red herring. There was a time, after all, when they thought the “canal” really were canals, and all the fuss over that mountain that looks a bit like a face still persists…

db

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